aware because it tends to prove the defendant’s reasonable belief, not the victim’s conduct..
4. Expert witnesses. Behavioral traits may not be proved by expert testimony from a
psychologist. This is a recurring issue in child sexual abuse cases, where the child’s testimony is
bolstered by her therapist, who testifies that the child is not prone to fantasy or exaggeration, is
not susceptible to manipulation by her mother, and has a tendency to be truthful.
E. Cross-Examination of Character Witnesses
1. Character witnesses who testify to a person’s reputation, or give their personal opinion,
concerning a character trait, may be cross-examined about whether they have heard about
specific acts that contradict the character trait testified to. If the witness states a personal opinion
about the defendant’s character, the prosecutor can ask the witness if they are personally aware of
the defendant’s prior convictions for disorderly conduct, assault and/or resisting law
enforcement. If the character witness testifies to reputation, the prosecutor can ask the witness
whether he or she has heard about the defendant's prior arrests for crimes of violence whether or
not they ended in convictions -- because we are talking about reputation, not fact. However,
before the state may raise any specific acts of a defendant on cross-examination, it must disclose
the acts it intends to use if the accused gave pretrial notice of intent to call character witnesses.
2. Character witnesses generally may not be asked hypothetical questions on cross-examination.
Thus, questions that begin, "Would your opinion of the defendant's character change if ..." are
improper. United States v. Williams, 738 F.2d 172 (7th Cir. 1984).
F. Bolstering
1. General rule. An attorney may not bolster the credibility of a witness with evidence of their
good character for truthfulness and honesty before that witness's credibility has been attacked.
The usual rationale for this rule is that every witness is presumed to speak the truth, so it is a
waste of time to accredit a witness unless it is clear that the witness's credibility is going to be an
issue, which we won’t know until the cross-examination.
2. Background evidence permitted. The no-bolstering rule does not prevent an attorney from
eliciting relevant background testimony from a witness, even if that background tends to enhance
the witness’s credibility. General background -- job, marriage, children, church, where one was
born and raised -- should always be admissible. The jury is entitled to know who the witness is.
In addition, more specific background should be permitted if it has something to do with the
case. For example, a police officer may testify to the number of years on the force, a small
business operator to the length of time in business, a doctor to the number of similar surgeries
performed., even though this may indirectly bolster the person's credibility or character. How-
ever, this rule should not be extended to allow testimony about unrelated good deeds.